Electrical trolley and conductor apparatus



Jun 17, 1958 R. w. BoLDT 2,839,621

ELECTRICAL TROLLEY AND CONDUCTOR APPARATUS Filed Feb. 25, 1953 I 0612 for I AM e a late btates ELECTRICAL TROLLEY AND CONDUCTOR APPARATUS Application February 25, 1953, Serial No. 338,782

1 Claim. (Cl. 191-33) lly invention relates to improvements in electrical trolleys and conductor apparatus and has particular application to mechanisms employed in cranes and load conveyors although not limited thereto.

Cne purpose is to provide a conductor bar which shall be eitective to conduct electricity while creating a minimum of resistance.

Another purpose is to provide a conductor bar which shall be light in weight, easy and economical to manufacture and which shall be reversible in operating position.

Another purpose is to provide improved connecting means for joining separate sections of conductor bars. which joining means shall be such as to provide a level surface with the longitudinal edges of adjacent conductor bar sections.

Another purpose is to provide connecting means for conductor bar sections which may be installed and the bars joined by manual operation alone and without the use or" special tools.

Another purpose is to provide securing means effective to retain adjacent conductor bar sections in general alignment.

Other purposes will appear from time to time in the course of the specification and claims.

I illustrate the invention more or less diagrammatically in the accompanying drawings, wherein:

Figure l is a side view illustrating the joining of adjacent ends of two conductor bars;

Figure 2 is a section on the line 2-2 of Figure 1;

Figure 3 is a side view illustrating a variant form of securing means;

Figure 4 is a section on the line 4-4 of Figure 3;

Figure 5 is a perspective view of a conductor bar section with connecting means;

Figure 6 is a perspective view of one form of securing means; and

Figure 7 is a side view of my connecting means.

Like parts are indicated by like symbols throughout the specification and drawings.

Referring now to the drawings, and particularly to Figure 1 thereof, 1 and 2 generally indicate end portions of conductor bar sections. A full conductor bar section is illustrated and numbered 3 in Figure 5. My conductor bar 3 is formed in what might be generally called a figure-eight configuration, as illustrated in Figures 2, 4 and 5. Flat, rectangular sheet stock, which may be bare, galvanized or copper clad steel, copper or other conductive material, is rolled into the form illustrated. The bar has an upper loop and a lower loop 5 which are equal in diameter and which are joined by the fiat portion 6 and the flat end portions 7 and 8 which together form a central web portion. it will be realized that the flat stock is bent upon itself to form the loops 4 and 5 and the longitudinal edges or side zones of the stock are brought together along the flat center portion or zone a to complete the conductor bar 3.

atent 2,839,621 Patented June 17, 1958 ltl'a i have tapered endwise faces 12 and 13, respectively. immediately adjacent the enlarged portion 11 are the threads 14 formed on the end portion 10b and 15 formed on the end portion 19a. The material of the threaded portions 14 and 15 is normally harder than that of which the conductor 3 is formed. The diameter of the end portions 10:: and 19b is such as to form a tight fit within the inside diameter of the loops l and 5 of the conductor bar 3.

In Figures 1 and 6 I illustrate one form of securing means whereby the adjacent sections of the conductor bar may be held in alignment after installation of the connecting means or pin 10. 16 illustrates an elongated generally flat bar or plate which may have a width substantially equal to the fiat portion 6 of the conductor bar 3. Extending outwardly from one face of the bar 15 are the posts 17 and 18 which are threaded adjacent their outer extremities. The conductor bar 3 has the apertures 17a and 18a located centrally between its longitudinal edges and adjacent its lateral edges. The apertures 17a and 13a are each spaced the same distance rom the lateral edges of the conductor bar 3. As will be best seen in Figure 6, the pins 17 and 18 are spaced apart along the bar 16 for a distance equal to twice the distance of one aperture from its adjacent lateral edge on the conductor bar 3, plus the width of the enlargement 11 on the connecting pin 10. When the posts 17 and 18 are inserted through the apertures adjacent opposing edges of connecting bar sections, as illustrated in Figure l, the nuts 1% and 18b are threaded onto the projecting ends of the posts, as illustrated in Figures 1 and 2.

in Figures 3 and 4-, l illustrate a variant form of securing means. indicates a clamp or U-shaped member which may be formed of spring steel or of insulating material, such as that used in well-known plastic insulators. The clamp 29 may be of sufficient length to extend substantially in both directions from the point at which opposing edges of consecutive conductor bar sections are connected. The clamp 20 has a generally circular body portion 21 which, before installation, has a diameter slightly less than the outer diameter of either of the loops 4 or in the conductor bar 3. The generally circular hody portion 21 has extensions 21a and 215 which in turn have outwardly bent edge portions 22 and 23 between which one of the loops 4 or 5 may be forced to permit installation of the securing means 20. When installed as will be seen in Figures 3 and 4, the depending portions 21a and 21b extend slightly beyond the mid-point between the longitudinal edges of the conductor bar 3.

It will be realized that, whereas, I have described and shown a practical and operative device, nevertheless many changes may be made in size, shape, number and disposition of parts without departing from the spirit of my invention. 1, therefore, wish my description and drawings to be taken as in a broad sense illustrative or diagrammatic, other than in limiting me to my specific showing herein.

The use and operation of my invention are as follows:

I provide a conductor bar which is light in weight, easy and economical to manufacture, and which may be reversed to permit a longer life in operation. Prior conductor bars have been formed of solid stock. The reduced amount of metal and increased surface area in my rolled steel figure-eight bar results in a much lighter weight. Since the loops 4 and 5 are symmetrical, the bar may be reversed. In operation, a trolley or collector having a roller-contact or shoe is caused to travel along the lower outer edge of the lower loop 5, considering the conductor bar as installed in accordance with the illustration of Figure 2. This causes wear and eventually the lower loop 5 becomes no longer serviceable. At this point my conductor bar may be reversed in position, the loop 4 now constituting the lower loop, which, of course, constitutes the replacement of a worn-out structure with a brand new one unworn duplicate.

In providing my rolled steel figure-eight bar, I also provide a conductor bar which lends itself to particularly advantageous methods of joining. The entire conductor structure of a particular installation may extend for many hundreds of feet throughout a factory or building. These conductor bars are normally supplied in sections of various lengths and shapes. The solid conductor bars used heretofore have been connected almost universally by a massive metal clamping structure, which was generally U-shaped. The solid U-shaped clamp was normally slipped over the upper portion of one conductor bar section and the adjacent bar section slipped into the extending portion of the clamp. A plurality of bolts were then screwed downwardly through the top of the clamp and against the upper portion of the conductor bars. Since the upper and lower loops of my conductor bar are, of course, hollow, they permit the use of my connector pin 10. In connecting adjacent sections of a conductor bar, it is a simple matter to insert the end portion a into the hollow center of the lower loop 5 and to insert the end portion 18b into the lower loop 5 of a second section of the conductor bar. The adjacent sections are held in the left and right hands, respectively, of the operator, who holds, for example, the right-hand section with the loop 4 below the loop 5, and the left-hand section in normal position with the loop 4 above the loop 5. Pressing the adjacent sections toward each other, the operator then twists the adjacent sections in opposite directions, forcing the threads 14 and 1.5 into the normally softer metal of the inside wall of the loops 5. The threads 14 and 15 are sufficient in number to insure that when the adjacent sections have been turned thereon up to the point of contact with the enlargement 11, said adjacent sections shall be in exact vertical alignment. The number of threads on each side of the enlargement 11 may, of course, be varied, depending upon the number of turns considered advisable before the adjacent conductor bar sections are brought into contact with the enlargement 11. With prior structures it is extremely diflicult to obtain initially, and virtually impossible to retain in operation, a close contact between the lateral edge por tions of adjacent conductor sections. The resulting gap caused an undesirable arcing as the trolley contact crossed over the open space. As will he observed in Figures 1 and 3, the enlargement 11, since it has an outer diameter exactly equal to the outer diameter of the loop 5, forms with the adjacent loops of the two joined sections a smooth surface, along which the electrical collector may run. This insures that arcing will not occur at the point of juncture.

While the threads 1415 will serve to rigidly grip and hold adjacent conductor Sections in position, the vibration and stresses to which the structure is subjected in operation are considerable. To insure that the adjacent sections do not get out of vertical alignment one with the other, I provide securing means in two forms.

When the lower loops 5 have been brought up snug with the enlargement 11 and the conductor bars vertically aligned, the posts 17 and 18 are inserted through the apertures, as illustrated in Figure 1, and the nuts 17]; and 1817 are threaded on the posts 17 and 18, to lock the adjacent bar sections in vertical alignment.

In the use of the securing means illustrated in Figures 3 and 4 a simple manual operation is involved. After the loops 5 of the adjacent conductor bar sections have been brought up snug to the enlargement 11 and the adjacent sections vertically aligned, the operator merely forces the clamp downwardly over the loops 4 of the joined sections. The outwardly turned lower edges of the depending portions 22, 23 of the securing means 28 facilitates the manual installation thereof and the material and shape of the securing means causes the depending portions 22, 23 to press continuously inwardly against the flat portion 6 and the fiat end portions '7 and 8 of the adjacent conductor bars.

I claim:

A conductor bar of sheet metal for electrical trolleys having a pair of hollow tubular loop portions and a central web portion interconnecting and between said tubular portions of a width greater than the internal diameter of said tubular portions, said web portion being of double thickness with one thickness being continuous and the other being split and having longitudinally extending side edges, said side edges lying side by side in close proximity to each other in said web portion between said tubular loop portions and the diameters of said hollow tubular portions being substantially equal whereby said tubular portions may be used interchangeably for contact with an electrical trolley by reversing the conductor bar to expose one or the other of said tubular portions to the trolley.

References Cited in the file of this patent UNITED STATES PATENTS 121,884 Miner Dec. 12, 1871 196,235 Knapp Oct. 16, 1877 261,370 McGlashan July 18, 1882 445,479 Short Jan. 27, 1891 471,625 Smith Mar. 29, 1892 885,864 Read Apr. 28, 1908 889,776 Dyer June 2, 1908 1,055,253 Benzel Mar. 4, 1913 1,109,968 Cowen Sept. 8, 1914 1,550,900 Goodspeed Aug. 25, 1925 1,828,008 Wennagel Oct. 20, 1931 2,240,954 Maloney et al. May 6, 1941 2,548,986 Mayer Apr. 17, 1951 2,618,845 Quarnstrom Nov. 25, 1952 2,668,199 Connell Feb. 2, 1954 2,704,309 Ford et al Mar. 15, 1955 FOREIGN PATENTS 134,509 Australia Oct. 6, 1949 

